Observe
1Physical Properties
Magnitude
4.68
Range
4.66 - 4.87
Variable Type
Semi-Regular Variable
Spectral Type
M5IIIb
bright giant
Star Color
Red
(B-V 1.69)
Distance
163 ly
2Position & Identifiers
RA
16h 20m 20.8s
Dec
-78° 41' 45.0"
Constellation
Apus
(Aps)
HR
6020
HIP
80047
HD
145366
SAO
257380
Bayer
Delta1
Variable ID
Del1 Aps
Querying VizieR catalog...
3How easy to spot?
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and configure your equipment and default location to see a personalized row.
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | Hard+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Survey Image
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Explore
6
Size Comparison
Querying VizieR for stellar data…
7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
Discover
14Stellar Notes
Lb? 4.66 - 4.87V.
Physical pair with HR 6021.
15
Light Travel Time Machine
16
Relativistic Travel
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
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1919 eclipse expedition confirming general relativity; first theory of stellar interiors; the Eddington limit
Biography
The Hertzsprung-Russell Diagram — Reading Stars Like a Map
The HR diagram turns the night sky into a physics map: every named star has a spot, every spot tells you mass, age, and fate. A guide for amateur observers.
Article
Apus
Mythology, bright stars, and deep-sky highlights.
Constellation
